Calling support

ts/util/callingPermissions.ts

@@ -0,0 +1,10 @@
+export async function requestCameraPermissions(): Promise<boolean> {
+  if (!(await window.getMediaCameraPermissions())) {
+    await window.showCallingPermissionsPopup(true);
+
+    // Check the setting again (from the source of truth).
+    return window.getMediaCameraPermissions();
+  }
+
+  return true;
+}